1. Field of the Invention
The present invention relates to a clothes dryer, and more particularly to a clothes dryer capable of circulating heated air to the inside of a drum and discharging the air which has dried clothes within the drum.
2. Description of the Background Art
Generally, a clothes dryer is an apparatus for automatically drying wet clothes after the clothes have been washed. The clothes dryer is installed separately from a washing machine and is typically classified as a dehumidifying-type or an exhausting-type clothes dryer.
The dehumidifying-type incorporates a method for drying clothes by condensing moisture circulating in the air in the drum, exhausting water generated by this condensing step to the outside of the dryer and supplying air to the inside of a drum heating the air. The exhausting-type incorporates a method for drying clothes by guiding external air of the dryer to the inside of the drum after drawing in and heating the air, and exhausting the air to the outside of the dryer again.
FIG. 1 is a view of an exhausting-type clothes dryer of the background art. FIG. 2 is a cross-sectional view taken along section line Axe2x80x94A of FIG. 1. The clothes dryer of the background art will be described in greater detail hereinafter. As seen in FIG. 1, the clothes dryer includes a case 1 having an input opening 1a on the front surface, a door 2 for opening and closing the input opening 1a of the case 1, a rotatable drum 3 installed in the case 1 for receiving clothes and having a plurality of baffles (not shown) protruding from an inner circumferential surface, a driving motor 4 and a transmission device 5 installed in the case 1 for rotating the drum. The dryer also includes an air circulation unit 7 for exhausting external air of the case 1 to the outside of the case 1 after circulating the air into the drum 3 and a heater 6 installed at the inlet side of the suction duct 7A of the above air circulation unit 7 for heating air circulated into the drum.
The drum 3 includes a body 3A that rotates while connected to the driving motor 4, the transmission device 5 and movable side plates 3B and 3C combined with the body 3A at both sides of the body 3A. The body 3A has a cylindrical shape and the baffles are formed on the circumferential surface at the inner side as a single body.
The side plates 3B and 3C are all formed in a circular plate shape and a suction port 3b connected with the suction duct 7A of the air circulation unit 7 is formed on the rear side plate 3B. The exhaust port 3c is formed on the front side plate 3C and is connected with an exhaust duct of the air circulation unit 7.
The driving motor 4 includes a single-direction rotary motor that rotates in the same direction and speed having a driving shaft extending in an axial direction. The transmission device 5 includes a pulley 5a combined with a driving shaft at a side of the driving motor 4 and a belt 5b connected from the pulley 5a to the body 3A of the drum 3 for transmitting the rotational force of the driving motor 4.
The heater 6 is installed at the inlet side of the suction duct 7A either adjacent to or combined with the inlet side. The heater can be a conventional electric heater or gas heater. The air circulation unit 7 includes the suction duct 7A for guiding air in the case 1 into the drum 3, the exhaust duct 7B for exhausting the air in the drum 3 to the outside of the case 1 and a fan 7C positioned at the center of the exhaust duct 7B for circulating air.
The suction duct 7A is installed to guide air that is heated while it passes the heater 6 after the air circulates to the inside through the air circulation port 1b of the case 1 to the inside of the drum 3. The inlet is positioned adjacent to or combined with the rear of the heater 6 and the outlet is connected with the suction port 3b of the drum 3. The exhaust duct 7B has an inlet connected to the suction port 3b of the drum 3 and the outlet extends to the outside penetrating the rear wall of the case 1.
The fan 7C is attached to a driving shaft of one side of the driving motor 4 that is also connected at a second side to the transmission device 5 in the exhaust duct 7B. The fan is a single inlet centrifugal fan having a suction side and an exhaust side respectively. In FIG. 1, a clothes input opening 3d of the drum and a filter F are also shown.
The operation of the clothes dryer of the background art with the above-described features will be described in greater detail hereinafter. When power is applied to the driving motor 4, the drum 3 is rotated by the belt 5b and clothes in the drum 3 are mixed. External air is heated as the fan 7C rotates, and the air is then supplied to the inside of the drum 3 and dries the wet clothes.
When the fan 7C is operated, the external air is drawn into the case 1 and the air is heated as it passes the heater 6. The heated air is then circulated to the inside of the drum 3 through the suction duct 7A and the suction port 3b. The heated air circulated within the drum dries the wet clothes and is then exhausted to the outside of the case 1 through the exhaust port 3c and the exhaust duct 7B.
However, since the suction port 3b of the drum 3 is formed having a simple punched-hole shape on the rear side plate 3B, heated air drawn into the inner side of the drum 3 moves to the side of the front side plate 3C along the upper portion of the inner circumferential surface of the drum 3 and is then exhausted. Therefore, the air is prevented from contacting the clothes positioned at the center portion of the drum 3. Accordingly, clothes in the drum 3 are not dried uniformly, clothes drying efficiency is reduced and the time for drying clothes is increased.
Further, when heated air flows into the drum 3 through the suction duct 7A, it tends to flow to the upper side. However, as shown in FIG. 2, since the suction port 3b formed on the rear side plate 3B is narrow at the upper side and wide at the lower side, air flow resistance is increased and the amount of air inflow for the same cross section of the suction port 3b is decreased, thereby decreasing clothes drying efficiency.
Since the suction duct 7A and the exhaust duct 7B are positioned at the front and rear sides of the drum 3, the volume of the drum 3 is decreased when compared to the volume of the same case 1. Since the volume of the drum 3 must be increased to dry larger amounts of clothes, the entire volume of the case 1 is disadvantageously increased.
Clothes may be efficiently dried when the direction and speed of rotation of the drum 3 is changed irregularly. However, since the clothes dryer of the background art described above drives the drum 3 and fan 7C simultaneously using a single driving motor 4, the fan is rotated in a single direction. Therefore, the drum 3 rotates only in one direction, and drying efficiency is decreased in the clothes dryer of the background art.
The present invention overcomes the shortcomings associated with the background art and achieves other advantages not realized by the background art.
Therefore, the present invention provides a clothes dryer capable of improving clothes drying efficiency by uniformly drying clothes inputted into a drum, wherein heated air is directly transmitted to the center portion of the drum.
Another object of the present invention is to provide a clothes dryer capable of decreasing the time required for drying clothes by increasing the amount of the heated air supplied into the drum.
Still another object of the present invention is to provide a clothes dryer capable of increasing the amount of laundry dried by increasing the volume of the drum without increasing the size of the case.
Still another object of the present invention is to provide a clothes dryer capable of improving drying efficiency by independently driving the drum and fan and varying direction and speed of rotation.
One or more of these and other objects of the present invention are accomplished by a clothes dryer comprising a case; a drum rotatably supported in the case and having a space for drying clothes within the drum; a suction duct being connected to a first side of the drum for supplying air to the drum for drying clothes; an extension duct extending from the suction duct into the drum, wherein air supplied from the suction duct into the drum flows through a plurality of air holes within the extension duct; and an exhaust duct being connected to a second side of the drum for exhausting air within the drum to an exterior of the case.
One or more of these and other objects of the present invention are also accomplished by a clothes dryer, comprising a case; a drum rotatably supported in the case and having a space for drying clothes within the drum; a suction duct being connected to a first side of the drum for supplying air to the drum for drying clothes; an extension duct extending from the suction duct into the drum, wherein air supplied from the suction duct into the drum flows through the extension duct; and an exhaust duct connected to a second side of the drum for exhausting air within the drum to an exterior of the case; wherein the drum has two air suction ports connected to the suction duct on a rear side of the drum and the extension duct is connected to a first air suction port of the two air suction ports.
One or more of these and other objects of the present invention are also accomplished by a clothes dryer comprising a case; a drum having a rotatable body supported in the case, and a front plate and a rear plate engaged with stationary front and rear sides of the body; a suction duct being connected to the rear plate of the drum supplying air to the drum for drying clothes; an extension duct extending from the suction duct into the drum, wherein air supplied from the suction duct into the drum flows through the extension duct toward a rotational center of the drum; and an exhaust duct connected to the front plate of the drum for exhausting air to an exterior of the case, wherein the front plate of the drum includes a cylindrical portion extending a certain length in a longitudinal direction of the body from an outer circumferential surface of the drum, the cylindrical portion having an exhaust port at a lower portion thereof, and the exhaust duct is connected to the exhaust port of the cylindrical portion.
One or more of these and other objects of the present invention are also accomplished by a clothes dryer comprising a case; a drum having a rotatable body supported in the case, and a front plate and a rear plate engaged with stationary front and rear sides of the body; a suction duct being connected to the rear plate of the drum supplying air to the drum for drying clothes; an exhaust duct being connected to the front plate of the drum for exhausting air to an exterior of the case; and an air suction port formed on the rear plate of the drum and connected to the air suction port, wherein the air suction port is formed having a tapered shape increasing in area as the air suction port extends away from a rotational center of the drum.
One or more of these and other objects of the present invention are is also accomplished by a clothes dryer, comprising a case; a drum rotatably supported in the case and having an interior space for drying clothes within the drum; a suction duct being connected to a first side of the drum supplying air to the drum for drying clothes; an extension duct extending from the suction duct into the drum, wherein air supplied from the suction duct into the drum flows through a plurality of air holes within the extension duct toward a rotational center of the drum; a first exhaust duct being connected to a second side of the drum for exhausting air within the drum to the outside of the case; and a second exhaust duct diverging from the first exhaust duct for exhausting a portion of the air exhausted from the drum to a front side of the suction duct.
Further scope of applicability of the present invention will become apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.